Question

Find the area of the triangle. Round the answer to the nearest tenth.

Answer 1

The answer is A. 68.4 square units. If you need an explanation I can write it down.

Answer 2

Answer:

Option A. 68.4 square units.

Step-by-step explanation:

Since sides ED = EF = 13 units

So the given triangle is an isosceles triangle and in an isosceles triangle EFD, perpendicular drawn from E to DF, will be perpendicular bisector of DF.

Moreover, to this perpendicular bisector to DF will be the height of the triangle.

Now Area of a triangle of $\frac{1}{2}$ × base × height.

Sin 63 =  $\frac{Height}{Hypotenuse}$ =  $\frac{h}{13}$

h = 13 sin 63 = 13 ( 0.891) = 11.583 units

Cos 63 =  $\frac{Base}{Hypotenuse}$ =  $\frac{Base}{13}$

Base = 13 cos 63 = 13 × (0.454)

                            = 5.90 units

Since DF = 2 × base = 2 × 5.90

                                 = 11.80 units

Now area of EDF =  $\frac{1}{2}$ × 11.80 × 11.583

                             = 68.86 ≈ 68.40 square units.

Option A. 68.4 square units.